<html><head><meta http-equiv="Content-Type" content="text/html; charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">I think he meant instead of the DAC, not to drive the backlight directly. I agree that would be asking for trouble. <div class=""><br class=""></div><div class="">Roman mentioned using a PWM pin as a basic DAC followed with a simple RC and the current sink, and that should be fine.<div class=""><div><br class=""><blockquote type="cite" class=""><div class="">On 30 Nov 2024, at 11:53, Mike Bryant <<a href="mailto:mbryant@futurehorizons.com" class="">mbryant@futurehorizons.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="elementToProof" style="font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt;">One problem is low cost displays aren't shielded so you'll transmit the PWM frequency everywhere</div><div id="appendonsend" style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""></div><div style="font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt;" class=""><br class=""></div><hr style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; display: inline-block; width: 764.390625px;" class=""><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class=""></span><div id="divRplyFwdMsg" dir="ltr" style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><span style="font-family: Calibri, sans-serif; font-size: 11pt;" class=""><b class="">From:</b> Synth-diy <<a href="mailto:synth-diy-bounces@synth-diy.org" class="">synth-diy-bounces@synth-diy.org</a>> on behalf of Gordonjcp <<a href="mailto:gordonjcp@gjcp.net" class="">gordonjcp@gjcp.net</a>><br class=""><b class="">Sent:</b> 30 November 2024 11:48<br class=""><b class="">To:</b> <a href="mailto:synth-diy@synth-diy.org" class="">synth-diy@synth-diy.org</a> <<a href="mailto:synth-diy@synth-diy.org" class="">synth-diy@synth-diy.org</a>><br class=""><b class="">Subject:</b> Re: [sdiy] current sink idea</span><div class=""> </div></div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-size: 11pt;" class="">On Sat, Nov 30, 2024 at 09:17:13AM +0100, Roman Sowa via Synth-diy wrote:<br class="">> with 2 days ago.<br class="">> Special needs require special solutions - I needed to control display's<br class="">> backlit intensity from internal DAC of the microcontroller, which<br class=""><br class="">Immediate first question - why not use a PWM pin?<br class=""><br class="">--<br class="">Gordonjcp<br class=""><br class="">________________________________________________________<br class="">This is the Synth-diy mailing list<br class="">Submit email to: <a href="mailto:Synth-diy@synth-diy.org" class="">Synth-diy@synth-diy.org</a><br class="">View archive at:<span class="Apple-converted-space"> </span><a href="https://synth-diy.org/pipermail/synth-diy/" id="OWAd66c2ba5-f495-4bae-d4eb-d82acbd181b2" class="OWAAutoLink" data-auth="NotApplicable">https://synth-diy.org/pipermail/synth-diy/</a><br class="">Check your settings at:<span class="Apple-converted-space"> </span><a href="https://synth-diy.org/mailman/listinfo/synth-diy" id="OWA87f2ce81-6f6d-0eba-b926-38752a660f7e" class="OWAAutoLink" data-auth="NotApplicable">https://synth-diy.org/mailman/listinfo/synth-diy</a><br class="">Selling or trading? Use <a href="mailto:marketplace@synth-diy.org" class="">marketplace@synth-diy.org</a></div><div id="appendonsend" style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""></div><div style="font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt;" class=""><br class=""></div><hr style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; display: inline-block; width: 764.390625px;" class=""><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class=""></span><div id="divRplyFwdMsg" dir="ltr" style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><span style="font-family: Calibri, sans-serif; font-size: 11pt;" class=""><b class="">From:</b> Synth-diy <<a href="mailto:synth-diy-bounces@synth-diy.org" class="">synth-diy-bounces@synth-diy.org</a>> on behalf of Gordonjcp <<a href="mailto:gordonjcp@gjcp.net" class="">gordonjcp@gjcp.net</a>><br class=""><b class="">Sent:</b> 30 November 2024 11:48<br class=""><b class="">To:</b> <a href="mailto:synth-diy@synth-diy.org" class="">synth-diy@synth-diy.org</a><span class="Apple-converted-space"> </span><<a href="mailto:synth-diy@synth-diy.org" class="">synth-diy@synth-diy.org</a>><br class=""><b class="">Subject:</b> Re: [sdiy] current sink idea</span><div class=""> </div></div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-size: 11pt;" class="">On Sat, Nov 30, 2024 at 09:17:13AM +0100, Roman Sowa via Synth-diy wrote:<br class="">> with 2 days ago.<br class="">> Special needs require special solutions - I needed to control display's<br class="">> backlit intensity from internal DAC of the microcontroller, which<br class=""><br class="">Immediate first question - why not use a PWM pin?<br class=""><br class="">--<br class="">Gordonjcp<br class=""><br class="">________________________________________________________<br class="">This is the Synth-diy mailing list<br class="">Submit email to:<span class="Apple-converted-space"> </span><a href="mailto:Synth-diy@synth-diy.org" class="">Synth-diy@synth-diy.org</a><br class="">View archive at:<span class="Apple-converted-space"> </span><a href="https://synth-diy.org/pipermail/synth-diy/" id="OWAb4d6ad37-1cad-8ee5-d85a-0196ec5e4e9d" class="OWAAutoLink" data-auth="NotApplicable">https://synth-diy.org/pipermail/synth-diy/</a><br class="">Check your settings at:<span class="Apple-converted-space"> </span><a href="https://synth-diy.org/mailman/listinfo/synth-diy" id="OWAa986eb13-3512-d8ca-17a5-4f946ce2faa2" class="OWAAutoLink" data-auth="NotApplicable">https://synth-diy.org/mailman/listinfo/synth-diy</a><br class="">Selling or trading? 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